Q VALUE AND THRESHOLD ENERGY

A colliison between reactant molecules must occur with a certain minimum energy before it is effective in yielding Product molecules. This minimum energy is called activation energy E_(a) Large the value of activation energy, smaller the value of rate constant k . Larger is the value of activation energy, greater is the effect of temperature rise on rate constant k . E_(f) = Activation energy of forward reaction E_(b) = Activation energy of backward reaction Delta H = E_(f) - E_(b) E_(f) = threshold energy The rate constant of a certain reaction is given by k = Ae^(-E_(a)//RT) (where A = Arrhenius constant). Which factor should be lowered so that the rate of reaction may increase?

A colliison between reactant molecules must occur with a certain minimum energy before it is effective in yielding Product molecules. This minimum energy is called activation energy E_(a) Large the value of activation energy, smaller the value of rate constant k . Larger is the value of activation energy, greater is the effect of temperature rise on rate constant k . E_(f) = Activation energy of forward reaction E_(b) = Activation energy of backward reaction Delta H = E_(f) - E_(b) E_(f) = threshold energy The activation eneries for forward and backward reactions in a chemical reaction are 30.5 and 45.4 kJ mol^(-1) respectively. The reaction is

The source of energy of stars is nuclear fusion. Fusion reaction occurs at very high temperature, about 10^(7) . Energy released in the process of fusion is due to mass defect. It is also called Q -value. Q = Delta mc^(2), Delta m = mass defect. Mass equivalent to the energy 931 MeV is

The source of energy of stars is nuclear fusion. Fusion reaction occurs at very high temperature, about 10^(7) . Energy released in the process of fusion is due to mass defect. It is also called Q -value. Q = Delta mc^(2), Delta m = mass defect. Fusion reaction takes place at about

A colliison between reactant molecules must occur with a certain minimum energy before it is effective in yielding Product molecules. This minimum energy is called activation energy E_(a) Large the value of activation energy, smaller the value of rate constant k . Larger is the value of activation energy, greater is the effect of temperature rise on rate constant k . E_(f) = Activation energy of forward reaction E_(b) = Activation energy of backward reaction Delta H = E_(f) - E_(b) E_(f) = threshold energy In a hypothetical reaction A rarr B , the activation energies for the forward and backward reactions are 15 and 9 kJ mol^(-1) , respectively. The potential energy of A is 10 kJ mol^(-1) . Which of the following is wrong?

A colliison between reactant molecules must occur with a certain minimum energy before it is effective in yielding Product molecules. This minimum energy is called activation energy E_(a) Large the value of activation energy, smaller the value of rate constant k . Larger is the value of activation energy, greater is the effect of temperature rise on rate constant k . E_(f) = Activation energy of forward reaction E_(b) = Activation energy of backward reaction Delta H = E_(f) - E_(b) E_(f) = threshold energy If a reaction A + B rarr C is exothermic to the extent 30 kJ mol^(-1) and the forward reaction has an activation energy of 249 kJ mol^(-1) the activation energy for reverse reaction in kJ mol^(-1) is

The energy profile diagram for the reaction: CO(g)+NO_(2)(g) hArr CO_(2)(g)+NO(g) is given below: The threshold energy of the reaction is

The photo electric threshold wavelength for a metal is 2750A^(@) , The minimum energy of a photon that can produce photoelectric effect in the metal is

The threshold frequency for a metallic surface correponds to an energy of 6.2 eV , and the stopping potential for a radiation incident on this surface 5 V . The incident radiation lies in

A metal sheet of silver is exposed to ultraviolet radiation of wavelength 1810A^(0) . The threshold wavelength of silver is 2640A^(0) Calculate the maximum energy of emitted electron.